A staircase in a wooden building is normally assembled and installed using a conventionally traditional method of construction.
Various methods of construction are used in the installation of a staircase in a wooden building. Among them, the most complicated method for construction relates to the assembly of a spiral staircase, which can only be implemented with the aid of the techniques of a carpenter.
Specifically, a spiral staircase installed in a wooden building includes a complicated framework, and a number of wooden members, joints, and the like, which require assembly. Specific methods for processing and working are required for such a complicated assembly of a spiral staircase, resulting in the problems of inefficiency in operation, a prolonged construction period, high costs, and the like, because the techniques of a professional carpenter are needed for such operations.
This invention has been proposed to solve the problems of the prior art and has an object of providing a spiral staircase and a connecting metal for the spiral staircase. The staircase can be connected and assembled simply, with certainty, and firmly without special carpenters techniques by using metals for connecting a shaft pole with the arm which is a tread of the spiral staircase, connection of the arm with a baluster, and connection of the baluster with a handrail, whereby low costs and high efficiency in operation can be achieved.